Nozzles, Nozzle Assemblies, and Related Methods

This application is a continuation-in-part of U.S. patent application Ser. No. 17/959,657, titled “NOZZLES, NOZZLE ASSEMBLIES, AND RELATED METHODS,” filed Oct. 4, 2022, which application is a continuation-in-part of U.S. patent application Ser. No. 17/713,161, titled “NOZZLES, NOZZLE ASSEMBLIES, AND RELATED METHODS,” filed Apr. 4, 2022, which application claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 63/171,718, titled “NOZZLES, NOZZLE ASSEMBLIES INCLUDING THE SAME, AND METHODS OF USING THE SAME,” filed Apr. 7, 2021, the disclosure of each of which is hereby incorporated by this reference in its entirety.

Three-dimensional (“3D”) printing is a method that includes dispensing a first layer of material onto a platform from a nozzle. Additional layers of material may be dispensed from the nozzle onto the first and subsequent layers until an object is formed. However, several issues exist with conventional nozzles and conventional nozzle assemblies that include the nozzles, such as unsatisfactory leaking of the material being dispensed and excessive wear on the nozzles.

Therefore, new and improved nozzles and nozzle assemblies including such nozzles are needed.

Embodiments are directed to nozzles for three-dimensional printing and related nozzle assemblies and methods of forming and using nozzles. In an embodiment, a nozzle for three-dimensional printing is disclosed. The nozzle may include at least one top surface, at least one bottom surface opposite the at least one top surface, at least one lateral surface, and at least one conduit surface extending from the at least one top surface to the at least one bottom surface. The at least one conduit surface defines a conduit. In some embodiments, at least a portion of the at least one conduit surface proximate to the at least one top surface is non-vertical. At least a portion of the at least one conduit surface includes at least one superhard material.

In an embodiment, a nozzle assembly for three-dimensional printing is disclosed. The nozzle assembly includes a base including an attachment portion configured to be attached to a printing device and a nozzle attached to the base. The nozzle may include at least one top surface, at least one bottom surface opposite the at least one top surface, at least one lateral surface, and at least one conduit surface extending from the at least one top surface to the at least one bottom surface. The at least one conduit surface defines a conduit. In some embodiments, at least a portion of the at least one conduit surface proximate to the at least one top surface is non-vertical. At least a portion of the at least one conduit surface includes at least one superhard material.

Some embodiments may include methods of forming and/or using the nozzles and nozzle assemblies.

For example, methods of forming a nozzle may include defining at least one conduit surface extending through the nozzle, extending at least a portion of the at least one conduit surface in a direction transverse to a central axis of the nozzle, and forming at least a portion of the at least one conduit surface with at least one superhard material.

In some embodiments, methods of using a nozzle in a three-dimensional printing process may include flowing a fluid (e.g., printing material) through a conduit of a nozzle defined by a conduit surface comprising at least one superhard material and directing fluid flow through the conduit with at least a portion of the conduit surface in a direction transverse to a central axis of the nozzle.

In some aspects, the techniques described herein relate to a method of forming a nozzle for use in a three-dimensional printing process, the method including: securing a material in a machining fixture; on a first side of the material, forming a hole into the material to define an at least partially conical inner conduit extending at least partially through the material; on a second side of the material, forming a through-hole into the material to define an exit orifice of the nozzle, the exit orifice connecting with the at least partially conical inner conduit to define a fluid pathway through the nozzle; defining the exit orifice to have a height extending in a direction along the fluid pathway of the nozzle and a width extending in a direction transverse to the height of the exit orifice, a ratio of the height relative to the width being substantially 1.2 or less; and forming an exterior of the nozzle to remove the nozzle from a remaining amount of the material.

In some aspects, the techniques described herein relate to a method of forming a nozzle for use in a three-dimensional printing process, the method including: on a first side of a material, forming a hole into the material to define an at least partially conical inner conduit extending at least partially through the material; reorienting the material to expose a second side opposing the first side; on the second side of the material, forming a through hole into the material to define an exit orifice of the nozzle, the exit orifice connecting with the at least partially conical inner conduit to define a fluid pathway through the nozzle; and forming an exterior of the nozzle to remove the nozzle from a remaining amount of the material.

In some aspects, the techniques described herein relate to a nozzle for three-dimensional printing, the nozzle including: at least one proximal surface defining an inlet of the nozzle; at least one distal surface opposite the at least one proximal surface, the at least one distal surface defining an outlet of the nozzle; at least one external surface extending from the at least one proximal surface to the at least one distal surface; and at least one conduit surface extending from the at least one proximal surface to the at least one distal surface, the at least one conduit surface defining a fluid flow conduit through the nozzle; wherein an interface between the at least one conduit surface and the at least one distal surface defines an exit orifice of the nozzle; and wherein the exit orifice exhibits a height extending in a direction along the fluid flow conduit and a width extending in a direction transverse to the height of the exit orifice, a ratio of the height relative to the width being substantially 1.2 or less.

Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings.

The present disclosure relates to nozzles for three-dimensional printing and related nozzle assemblies and methods of forming and using the nozzles. An example nozzle includes at least one top surface, at least one bottom surface, and at least one lateral surface extending from or near the top surface to or near the bottom surface. The nozzle also includes at least one conduit surface defining a conduit. The conduit surface extends from or near the top surface to or near the bottom surface. In an embodiment, at least a portion of the conduit surface most proximate to the top surface is non-vertical (e.g., forms a non-cylindrical or non-rectangular shape, extends along an axis that is transverse to a central axis of the nozzle). In such an embodiment, the conduit surface is non-vertical when the conduit surface is not parallel (e.g., transverse) to a central axis of the nozzle extending from the top surface to the bottom surface.

Features of the nozzles disclosed herein may be configured to, for example, reduce the force required to push a printing material through the conduit, facilitate removal of a first printing material to prevent contamination of a second, different printing material that may subsequently flow through the conduit, prevent clogging of the conduit, improve heating of the printing material flowing through the nozzle, improve resolution of the printed material, and/or improve adhesion of different layers of the printed material. These features may be useful when flowing any printing material through the conduit but may be especially useful when an abrasive printing material flows through the nozzle. Abrasive printing materials may include printing materials exhibiting a hardness that is comparable to or greater than brass, steel, or other materials that are commonly used to form nozzles. Examples of abrasive printing materials include polymers with one or more particles (e.g., ceramic particles, metal particles, carbon fiber, etc.) disposed there

n, a ceramic, a metal, a composite, or combinations thereof. It is noted that, as used herein, “printing material” refers to the material flowing through the conduit (e.g., a fluid or otherwise flowable material) and “printed material” refers to the material that has been dispensed from the nozzle.

The features of the nozzle disclosed herein may form features that are more likely to be worn away when the abrasive printing material flows through the conduit thereby reducing the benefits of the features disclosed herein. As such, in some embodiments, the nozzles disclosed herein may be at least partially comprise (or be formed from) at least one of polycrystalline diamond (“PCD”), polycrystalline cubic boron nitride (“PcBN”), another superhard material exhibiting a hardness that is equal to or greater than tungsten carbide, and/or a combination of any of the foregoing. For example, the nozzles may be formed such that the features of the nozzles disclosed herein may be defined by and/or formed by PCD, PcBN, or another superhard material. Further, it is noted that forming at least a portion of the nozzles disclosed herein from at least one of PCD or PcBN may improve the thermal conductivity of the nozzle thereby improving heating of the printing material than if the nozzle was formed from another superhard material.

As used herein, relational terms, such as “first,” “second,” “top,” “bottom,” etc., are generally used for clarity and convenience in understanding the disclosure and accompanying drawings and do not connote or depend on any specific preference, orientation, or order, except where the context clearly indicates otherwise.

As used herein, the term “and/or” means and includes any and all combinations of one or more of the associated listed items.

As used herein, the terms “vertical,” “upper,” “lower,” and “lateral” refer to the orientations as depicted in the figures.

is an isometric view of a nozzle, according to an embodiment.is a cross-sectional schematic of the nozzletaken along planeB-B shown in, according to an embodiment. The nozzleincludes at least one top surface, at least one bottom surfaceopposite the top surface, at least one lateral surface, and, optionally, one or more chamfers (e.g., chamfer). In the illustrated embodiment, the lateral surfaceextends from the top surfaceto a location that is near the bottom surface(e.g., to the chamferextending between the bottom surfaceand the lateral surface). However, it is noted that the lateral surfacemay at least one of extend from a location that is near the top surfacewhen the nozzleincludes an outer chamfer extending between the top surfaceand the lateral surfaceor to the bottom surfacewhen the chamferis omitted. The nozzlealso includes at least one conduit surfacedefining a conduit. At least a portion of the conduit surfacemay include at least one superhard material exhibiting a hardness that is equal to or greater than tungsten carbide. Such a configuration may limit wear of the conduit surface. In an embodiment, as illustrated, the conduit surfaceextends from the top surfaceto the bottom surface. However, the nozzlemay include one or more chamfers extending from at least one of the top surfaceor the bottom surfaceto the conduit surface. The top surfaceand/or the conduit surfacedefine an orificethrough which the printing materials are dispensed from the nozzleand the bottom surfaceand/or the conduit surfacedefine an openingthrough which the conduitmay receive the printing material.

As previously discussed, the top surfaceof the nozzle defines the orifice. The orificemay exhibit a maximum lateral dimension (e.g., diameter) that is about 0.25 mm, about 0.4 mm, about 0.6 mm, about 0.8 mm, about 1.0 mm, about 0.1 mm or greater, about 0.2 mm or greater, about 0.4 mm or greater, about 0.6 mm or greater, about 0.8 mm or greater, about 1 mm or greater, about 1.5 mm or greater, about 2 mm or greater, about 3 mm or less, about 2 mm or less, about 1 mm or less, about 0.75 mm or less, about 0.5 mm or less, or in ranges of about 0.1 mm to about 0.3 mm, about 0.2 mm to about 0.4, about 0.3 mm to about 0.5 mm, about 0.4 mm to about 0.6 mm, about 0.5 mm to about 0.7 mm, about 0.6 mm to about 0.8 mm, about 0.7 mm to about 0.9 mm, about 0.8 mm to about 1 mm, about 0.9 mm to about 1.5 mm, about 1 mm to about 2 mm, or about 1.5 mm to about 3 mm. The maximum lateral dimension of the orificemay affect the achievable resolution of the printed material and rate at which the nozzlemay dispense the printing material. For example, increasing the maximum lateral dimension of the orificemay increase the rate at which the nozzlemay dispense the printing material but may decrease the achievable resolution of the printing material.

The top surfacemay exhibit a surface area that is about 0.075 mmor greater, about 0.1 mmor greater, about 0.2 mmor greater, about 0.3 mmor greater, about 0.5 mmor greater, about 0.7 mmor greater, about 1 mmor greater, about 1.25 mmor greater, about 1.5 mmor greater, about 2 mmor greater, about 3 mmor greater, about 4 mmor greater, or in ranges of about 0.075 mmto about 0.2 mm, about 0.1 mmto about 0.3 mm, about 0.2 mmto about 0.4 mm, about 0.3 mmto about 0.5 mm, about 0.4 mmto about 0.6 mm, about 0.5 mmto about 0.7 mm, about 0.6 mmto about 0.8 mm, about 0.7 mmto about 0.9 mm, about 1 mmto about 1.25 mm, about 1 mmto about 1.5 mm, about 1.25 mmto about 1.75 mm, about 1.5 mmto about 2 mm, about 1.75 mmto about 3 mm, or about 2 mmto about 4 mm. In an example, the surface area of the top surfacemay be selected based on the maximum lateral dimension of the orificesince increasing the maximum lateral dimension of the orificemay result in an increase of the surface area of the top surface. In an example, the surface area of the top surfacemay be selected to be a relatively small which may decrease the likelihood that the top surfacecontacts the printed material during use and/or decrease the adverse effect (e.g., smudging, dragging, or flattening) of the top surfacecontacting the printed material.

In an embodiment, as illustrated, the top surfacemay be generally planar. In an embodiment, at least a portion of the top surfacemay be non-planar, such as curved or tapered. The top surfacethat is at least partially curved or tapered may decrease the likelihood that the top surfacecontacts the printed material during use. For example, the nozzle assembly (illustrated in) may not extend perpendicular to the printed material. The curved or tapered portions of the top surfacemay prevent portions of the top surfacefrom contacting the printed material that would otherwise protrude or be more likely to contact the printed material if the top surfacewas planar due to the non-perpendicular angle ϕf the printing system relative to the printed material.

The bottom surfaceis configured to contact one or more surfaces of the base (“base contact surface”). An example of the base contact surface is base contact surfaceof. The bottom surfacemay exhibit a surface topography that generally corresponds to base contact surface. For example, the bottom surfacemay exhibit a generally planar topography when base contact surface is also generally planar. Selecting the bottom surfaceto exhibit a surface topography that generally corresponds to the base contact surface may reduce the size of gaps present between the bottom surfaceand the base contact surface. Gaps present between the bottom surfaceand base contact surface may allow printing material to leak between the bottom surfaceand the base contact surface. The printing material leaking between the bottom surfaceand the base contact surface may result in material being discharged from a portion of the nozzle assembly other than the orifice. The printing material leaking between the bottom surfaceand the base contact surface may also result in contamination of the printed material. For example, the leaked printing material may be cured or compositionally differently than a printing material subsequently flowing through the conduit, the mixing of either of which with the printing material flowing through the conduitmay result in printing flaws. In an embodiment, the bottom surfacemay be generally parallel to the top surface.

At least a portion of the lateral surfaceis non-vertical (e.g., extends in a plane that would intersect a central axisof the nozzle). The lateral surfacemay be non-vertical, for example, when the lateral surfaceis non-parallel (e.g., transverse) to the central axisof the nozzle(e.g., an axis that extends from a center of the top surfaceto a center of the bottom surface). For example, at least about 55%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, about 100% (as shown), or in ranges of about 55% to about 70%, about 60% to about 80%, about 70% to about 90%, or about 80% to about 100% of the lateral surfaceis non-vertical. The percentage of the lateral surfacethat is non-vertical may relate to the percentage of at least one of the surface area, the percentage of the length LN of the nozzlealong which the lateral surfaceis non-vertical, or a length of the lateral surfacemeasured along a shortest path from the top surfaceto the bottom surface(including or excluding any chamfers) that extends along an exterior of the lateral surfacethat is non-vertical. Selecting the percentage of the lateral surfacethat is non-vertical to be greater than 55% and, further, increasing the percentage of the lateral surfacethat is non-vertical may facilitate attachment of the nozzleto a base. For example, as will be discussed in more detail below, the nozzlemay be positioned within a recess defined in the base and may be attached to the base. The recess may define a recess opening (e.g., after swaging) that is less than one or more dimensions (e.g., less than a maximum lateral dimension DN) of the nozzlewhich prevents the nozzlefrom leaving the recess and secures the nozzleto the base. Increasing the percentage of the lateral surfacethat is non-vertical may allow more of the lateral surfaceto be contacted by the surfaces of the base that define the recess thereby better securing the nozzleto the recess. Further, increasing the percentage of the nozzlethat is non-vertical, such as portions of the nozzlethat are more proximate to the bottom surface, increases the distance that the top surfacemay protrude from the base. Examples of the angles that the lateral surfacemay extend relative to the central axisare disclosed in U.S. Provisional Patent No. 63/171,708, filed on Apr. 7, 2021, the disclosure of which is incorporated herein, in its entirety, by this reference.

In an embodiment, the lateral surfaceincludes a generally conically shaped surface. However, the lateral surfacemay include a plurality of surfaces or a non-conical surface, without limitation. In an example, the lateral surfacemay include a plurality of surfaces, wherein an angle that each surface of the lateral surfaceextends relative to the central axismay be different. The plurality of lateral surfacesmay facilitate attachment of the nozzleto the base and may increase the distance that the top surfaceof the nozzlemay extend above the base. In an example, at least a portion of the lateral surfacemay exhibit a generally prism shape, a generally frustum shape, a generally cylindrical shape, or any other suitable shape.

As previously discussed, the nozzleincludes the chamferextending from the bottom surfaceto the lateral surface. Any of the chamfers disclosed herein include one or more transitional surfaces between two other surfaces and, except as otherwise disclosed herein, may include one or more rounded surfaces (e.g., a rounded surface exhibiting an average radius of curvature that is greater than about 0.025 mm, greater than about 0.05 mm, greater than about 0.1 mm, or greater than about 0.2 mm) and/or one or more planar surfaces. The chamfermay facilitate insertion of the nozzleinto a recess defined by the base to which the nozzleis attached in comparison to insertion of the nozzleif such nozzleincluded a sharp corner (e.g., a surface exhibiting an average radius of curvature that is less than 0.2 mm) between the bottom surfaceand the lateral surface.

At least a portion of at least one of the top surface, the bottom surface, the lateral surface, or any other exterior surface of the nozzle(e.g., the chamfer) may be polished to exhibit a root mean square (“RMS”) surface roughness that is about 3 μm or less, about 2 μm or less, about 1.5 μm or less, about 1 μm or less, about 750 nm or less, about 500 nm or less, about 300 nm or less, about 200 nm or less, about 100 nm or less, about 75 nm or less, about 50 nm or less, about 30 nm or less, about 15 nm or less, or about 15 nm to about 50 nm, about 30 nm to about 75 nm, about 50 nm to about 100 nm, about 75 nm to about 200 nm, about 100 nm to about 300 nm, about 200 nm to about 500 nm, about 300 nm to about 750 nm, about 500 nm to about 1 μm, about 750 nm to about 1.5 μm, about 1 μm to about 2 μm, about 1.5 μm to about 3 μm. In an example, decreasing the RMS surface roughness of at least a portion of the top surfacemay decrease the coefficient of friction between the polished portion of the top surfaceand the printed material. As such, the polished portion of the top surfacemay be less likely to pull portions of the printed material in the direction that the nozzlemoves relative to the printed material when the top surfacecontacts the printed material. In an example, contacting a polished portion of the top surfaceagainst the printed material may cause the top surfaceto impart a smooth surface to the printed material which may be used to influence (e.g., improve) the deposition of the next layer of printed material on the already printed material and/or may impart a desired shape to the printed material. In an example, polishing the bottom surfaceand/or the lateral surfaceto any of the RMS surface roughness discussed above may reduce gaps between the bottom surfaceand/or the lateral surfaceand the base that would otherwise form therebetween. Reducing gaps between the bottom surfaceand/or the lateral surfaceand the base may prevent or inhibit the printing material leaking between the nozzleand the base.

Referring to, the conduit surfaceincludes a portion that is closest to the top surface(“top portion of the conduit surface”). The top portion of the conduit surfaceincludes the portion of the conduit surfacethat extends a non-zero distance from the top surface(e.g., first conduit surface) and/or a chamfer extending between the top surfaceand the conduit surface(e.g., chamferorillustrated in). For example, the distance that the top portion of the conduit surfaceextends may be at least about 0.25 mm, at least about 0.5 mm, or at least about 1 mm.

A portion of the conduit surface(e.g., the top or upper portion proximate the orifice) may be non-vertical (e.g., extends in a plane that would intersect a central axisof the nozzle). For example, where the cross-section of the top portion of the conduit surfaceis non-parallel (e.g., set transverse) to a central axisof the nozzle. Stated in another way, the portion of the conduit surfacemay extend laterally or radially inward and/or laterally or radially outward relative to the central axis. Such portions of the conduit surfaceset and extending at one or more oblique angles relative to the central axismay define surfaces that gradually expand or contract the cross-section volume of the orifice.

As such, the top portion of the conduit surfacemay not exhibit a generally cylindrical shape or a generally rectangular shape since such shapes include vertical surfaces (e.g., aligned with the central axis). Surprisingly, it has been found that the non-verticality of the top portion of the conduit surfacemay decrease the force required to push the printing material through the conduitin comparison to the force required to push the printing material through the conduit if the top portion of the conduit surfacewere vertical. The non-verticality of the top portion of the conduit surfaceallows a more gradual reduction of a width (e.g., measured perpendicular to the central axis) of the conduitthan if the top portion of the conduit surfacewere vertical. It is currently believed that, at least in part, a gradual reduction in the width of the conduitmay decrease the force required to move the printing material through the conduit. The decreased force required to push the printing material through the conduitmay also decrease the likelihood that the printing material leaks between the nozzleand the base. It has also been surprisingly found that the non-verticality of the conduitmay reduce the likelihood that the conduitbecomes clogged while flowing the printing material through the conduit.

Further, unexpectedly, it has been found that the non-verticality of the top portion of the conduit surfacemay allow for more complete removal of the printing material from the conduit. The printing material may be removed from the conduit, for example, after completing a printing process to prevent the printing material that remains in the conduitfrom drying, solidifying, or clogging the conduitthereby preventing further use of the nozzle. Alternatively, or additionally, the printing material may be removed from the conduitafter printing a first material from the nozzleand before printing a second material from the nozzlethat is different than the first material to prevent the first printing material from contaminating the second material. It has been found that, when the top portion of the conduit surfaceis vertical, removing the printing material from the conduitresults in the formation of strings of printing material in and extending from the conduit. At least some of the strings of the printing material may remain in the conduitafter removing the rest of the printing material and the strings of the printing material that remain in the conduitmay be difficult to completely remove from the conduit. However, unexpectedly, it has been found that the non-verticality of the top portion of the conduit surfaceprevents the formation of the strings of printing material or at least decreases the quantity of the strings of printing material that form as compared to the quantity of strings of printing material that would form if the top portion of the conduit surfacewere vertical. Further, if strings of printing material form when removing the printing material, the non-verticality of the top portion of the conduit surfaceallows more of the strings to be removed from conduitthan if the top portion of the conduit surfacewere vertical. Not wishing to be bound by any theory, it is currently believed that, when the conduit surfaceincludes a plurality of conduit surfaces, the intersections (i.e., corners or edges) between different surfaces of the conduit surfacecauses the formation of the strings. The non-verticality of the top portion of the conduit surfacemay make the intersections between different surface of the conduit surfaceless pronounced (e.g., the difference between the angles θ and $ is smaller) than if the top portion of the conduit surfacewas vertical. It is believed that the less pronounced intersections formed due to the non-verticality of the top portion of the conduit surfacereduces the formation of strings and allows for more complete removal of the printing material than if the top portion of the conduit surfacewas vertical. It is noted that the less pronounced intersections may also reduce the force required to push the printing material through the conduitand reduce the likelihood that the printing material becomes clogged during operation.

As illustrated in, the conduit surfaceincludes a first conduit surfaceand a second conduit surface. The first conduit surfaceextends from the top surface(as shown) or may extend from a chamfer extending between the top surfaceand the conduit surface(as shown in) to the second conduit surface. The second conduit surfaceextends from the first conduit surfacetowards (e.g., to) the bottom surface(as shown). Configuring the conduit surfaceto include a plurality of surfaces makes the edges formed between such surfaces less pronounced. The conduit surfaces will make the edges formed between the conduit surfaceand the bottom surfaceless pronounced. Thus, the plurality of conduit surfacesmay provide one or more of the following benefits: reduce the force required to push the printing material through the conduit; reduce the likelihood that the printing material becomes clogged during operation; and/or prevent or decrease the likelihood that strings of printing material are formed when removing the printing material from the conduitas compared to the likelihood that strings of printing material would be formed if the conduit surfaceonly included a single conduit surface.

In the illustrated embodiment, the first conduit surfacemay at least partially form the top portion of the conduit surface. As such, the first conduit surfacemay be non-vertical. In an example, as illustrated, the first conduit surfacemay form a generally frustoconical shape. In such an example, the first conduit surfacemay extend at an angle θ relative to the central axis. In an example, the first conduit surfacemay exhibit a generally converging shape (e.g., a generally tapered shape with a curved side wall, such as a side wall that forms a concave or convex shape when viewed in cross-section), a truncated generally polyhedron shape (e.g., the walls of the truncated generally polyhedron shape may extend at the angle θ relative to the central axis), or any other suitable shape. It is noted that the generally truncated generally polyhedron shape and other shapes that the first conduit surfacemay include intersecting surfaces that may increase the formation of strings of the printing material when removing the printing material than if the first conduit surfaceexhibited intersecting surfaces, such as a frustoconical shape or a generally converging shape. However, such edges of such shapes may be less likely to form strings of the printing material when removing the printing material than if the first conduit surfaceexhibited a generally cylindrical shape or another shape.

It is noted that, in some embodiments, the first conduit surfacemay exhibit a shape that includes non-vertical and vertical surfaces, such as a truncated generally triangular prism shape. Such shapes may increase (compared to shapes that only include vertical surfaces) and decrease (compared to shapes that do not include vertical surfaces) the force required to push the printing material through the conduit, the likelihood that the printing material becomes clogged, and/or the likelihood that strings of printing material are formed when removing the printing material from the conduit.

When the first conduit surfaceextends at an angle θ relative to the central axis(e.g., the first conduit surfaceexhibits a truncated generally conical or polyhedron shape), the angle θ may be selected to be about 1° or greater, about 2° or greater, about 3° or greater, about 4° or greater, about 5° or greater, about 6° or greater, about 7° or greater, about 8° or greater, about 9° or greater, about 10° or greater, about 12° or greater, about 14° or greater, about 18° or greater, about 20° or greater, about 25° or greater, about 30° or greater, about 35° or greater, about 40° or greater, about 45° or greater, or in ranges of about 1° to about 3°, about 2° to about 4°, about 3° to about 5°, about 4° to about 6°, about 5° to about 7°, about 6° to about 8°, about 7° to about 9°, about 8° to about 10°, about 9° to about 12°, about 10° to about 14°, about 12° to about 16°, about 14° to about 18°, about 16° to about 20°, about 18° to about 25°, about 20° to about 30°, about 25° to about 35°, about 30° to about 40°, or about 35° to about 45°. The angle θ may be selected based on one or more factor. In an example, the angle θ may be selected to be greater than about 4° since the first conduit surfacemay start behaving similar to a vertical conduit surface when the angle θ is less than 4°. As used herein, the term “vertical” means the angle θ is between 0° and 1°. In an example, the angle θ may be selected based on the method used to form the conduit, since some methods of forming the conduitmay only be able to form the first conduit surfaceat certain angles θ relative to the central axis. In an embodiment, the angle θ may be selected based on the angle ϕ that the second conduit surfaceextends relative to the central axissince, generally, the angle ϕ may be selected to be greater than the angle θ, which may decrease the force required to push the printing material through the conduit.

The second conduit surfacemay also be non-vertical, thereby allowing the width of the conduitto generally decrease along a path of the conduitfrom the openingto the orifice. In an example, the non-verticality of the second conduit surfacemay form a truncated generally conical shape. In such an example, the second conduit surfacemay extend at an angle ϕrelative to the central axis. In an example, the second conduit surfacemay exhibit a generally converging shape, a truncated generally polyhedron shape, a generally frustoconical shape, or any other suitable shape. The second conduit surfacemay form the same or different shape as formed by the first conduit surface

When the second conduit surfaceextends at an angle ϕrelative to the central axis(e.g., the second conduit surfaceexhibits a truncated generally conical or generally polyhedron shape), the angle ϕ may be selected to be about 5° or greater, about 6° or greater, about 7° or greater, about 8° or greater, about 9° or greater, about 10° or greater, about 12° or greater, about 14° or greater, about 18° or greater, about 20° or greater, about 25° or greater, about 30° or greater, about 35° or greater, about 40° or greater, about 45° or greater, about 50° or greater, about 55° or greater, about 60° or greater, about 65° or greater, about 70° or greater, or in ranges of about 5° to about 7°, about 6° to about 8°, about 7° to about 9°, about 8° to about 10°, about 9° to about 12°, about 10° to about 14°, about 12° to about 16°, about 14° to about 18°, about 16° to about 20°, about 18° to about 25°, about 20° to about 30°, about 25° to about 35°, about 30° to about 40°, about 35° to about 45°, about 40° to about 50°, about 45° to about 55°, about 50° to about 60°, about 55° to about 65°, or about 60° to about 70°. The angle ¢ may be selected based on one or more factor. In an example, the angle ϕ may depend on the angle θ of the first conduit surfacesince, as previously discussed, the angle ϕ is selected to be greater than the angle θ. In an example, the angle ϕ may be selected such that the openingexhibits a size comparable to the size of the passageway of the base (e.g., passagewayof). In such an example, the angle ϕ may also be selected based on the length LN of the nozzleand the length that the first conduit surfaceextends along the central axissince these factors may affect the angle ¢ needed to form an openingexhibiting a size comparable to the size of the passageway of the base.

is an enlarged view of the portion of the nozzlewithin the circleC illustrated in, according to an embodiment. As shown in, the first and second conduit surfaces,may meet at an intersection. As previously discussed, the intersectionmay cause the formation of strings of the printing material when removing the printing material from the conduit. The intersectionmay be rounded, which makes the intersectionless pronounced and may reduce the likelihood that the intersectioncauses the formation of the strings of the printing material when the printing material is removed from the conduitthan if the intersectionwas not rounded. The intersectionmay be rounded when the intersectionexhibits a radius of curvature that is about 0.1 mm or greater, about 0.15 mm or greater, about 0.2 mm or greater, about 0.3 mm or greater, about 0.4 mm or greater, about 0.5 mm or greater, about 0.6 mm or greater, about 0.7 mm or greater, about 0.8 mm or greater, about 0.9 mm or greater, about 1 mm or greater, or in ranges of about 0.1 mm to about 0.2 mm, about 0.15 mm to about 0.3 mm, about 0.2 mm to about 0.4 mm, about 0.3 mm to about 0.5 mm, about 0.4 mm to about 0.6 mm, about 0.5 mm to about 0.7 mm, about 0.6 mm to about 0.8 mm, about 0.7 mm to about 0.9 mm, or about 0.8 mm to about 1 mm. Generally, increasing the average radius of curvature of the intersectionmay reduce the likelihood that the intersectioncauses the formation of the strings of the printing material.

is an enlarged view of the portion of the nozzlewithin the circleC illustrated in, according to another embodiment. As shown in, the first and second conduit surfaces,meet at an intersection′ that is not rounded. The intersection′ is not rounded when the intersection′ exhibits an average radius of curvature that is less than 0.1 mm. The non-rounded intersection′ may increase the likelihood that the intersection′ causes the formation of strings of printing material when the printing material is removed from the conduitcompared to the intersectionillustrated in. However, forming the intersection′ may reduce the amount of manufacturing effort required to form the nozzlecompared to forming the intersectionillustrated in. Further, the intersection′ forms a feature when the printing material flows through the conduitsuch that the intersection′ may be likely to wear at a greater rate than the rest of the nozzle. The wearing of the intersection′ may cause the intersection′ to become rounded relatively quickly thereby reducing the likelihood that the intersection′ causes the formation of strings of the printed material.

The conduit surfaces disclosed herein may include three or more conduit surfaces, such as a first conduit surface, a second conduit surface, and at least one additional conduit surface (e.g., third conduit surface). The first conduit surface may extend from or near the top surface of the nozzle to the second conduit surface, the second conduit surface may extend between the first conduit surface and the at least one additional conduit surface, and the at least one additional conduit surface may extend from the second conduit surface to or near the bottom surface.is a cross-sectional schematic of a nozzle, according to an embodiment. Except as otherwise disclosed herein, the nozzlemay include one or more features which are the same or substantially similar to any of the one or more features of other nozzle embodiments disclosed herein, without limitation. For example, the nozzlemay include a top surface, a bottom surface, at least one lateral surface, and a plurality of conduit surfacesdefining a conduit.

The conduit surfacesof the nozzleincludes a first conduit surface, a second conduit surface, and a third conduit surface. Inclusion of the third conduit surfacefurther makes the edges formed between the conduit surfacesless pronounced thereby decreasing the quantity of strings of material formed when removing the printing material and decreases the force required to push the printing material through the conduit.

The first conduit surfaceextends from or near the top surfaceat an angle θ relative to the central axis. The second conduit surfaceextends between the first and third conduit surfaces,at an angle ϕrelative to the central axisthat is greater than the angle θ. The third conduit surfaceextends from the second conduit surfacetowards (e.g., to or near) the bottom surfaceat an angle α relative to the central axisthat is greater than the angle ϕ. The angles θ, ϕ, and a may include any of the angles discussed above.

It is noted that the nozzlemay include one or more additional conduit surfaces in addition to the first, second, and third conduit surfaces,,. The addition conduit surface(s) may extend from the third conduit surfacetoward (e.g., to or near) the bottom surface. The additional conduit surfaces may further decrease the edges formed between the conduit surfacesthereby decreasing the quantity of strings of material formed when removing the printing material and decreases the force required to push the printing material through the conduit.

As previously discussed, the conduit surfaces disclosed herein may include a curved surface, such as a convex and concave curved surface.each show a cross-sectional view of different nozzle embodiments, each including curved conduit surfaces. Except as otherwise disclosed herein, the nozzles illustrated inmay include one or more features which are the same or substantially similar to any of the one or more features nozzles disclosed herein, without limitation. For example, the nozzles may include a top surface, a bottom surface, a lateral surface, and a conduit surface defining a conduit.

Referring to, the nozzlemay include a conduit surfaceexhibiting a convex curvature. The convex curvature of the conduit surfacemay be configured to allow the conduit surfaceto have only non-vertical surface(s) at a top portion of the conduit surface. As such, the conduit surfacemay provide one or more of the following: decreasing the likelihood that the printing material clogs the conduit; decreasing the pressure required the push the printing material through the conduit; or decreasing the likelihood that strings of the printing material are formed while removing the printing material from the conduitthan if the conduit surfaceincluded a vertical surface. In some embodiments, the lateral dimension at and near the openingdecreases at a greater rate than if the conduit surfaceexhibited a truncated conical shape as shown in. The greater change of the lateral dimension at and near the openingmay increase the force required to move the printing material through the conduitnear the openingthan if the conduit surfaceexhibits a truncated conical shape.

Referring to, the nozzlemay include a conduit surfaceexhibiting a concave curvature. The concave curvature of the conduit surfacemay be configured to allow the conduit surfaceto have only non-vertical surface(s) at a top portion of the conduit surface. As such, the conduit surfacemay provide one or more of the following: decreasing the likelihood that the printing material clogs the conduit; decreasing the pressure required the push the printing material through the conduit; or decreasing the likelihood that strings of the printing material are formed while removing the printing material from the conduitthan if the conduit surfaceincluded a vertical surface. In some embodiments, the lateral dimension at and near the orificedecreases at a greater rate than if the conduit surfaceexhibited a truncated conical shape as shown in. The greater rate of change of the lateral dimension at and near the orificemay increase the force required to move the printing material through the conduitnear the orificethan if the conduit surfaceexhibits a truncated conical shape.

During operation of any of the nozzles disclosed herein, the printing material may be heated to maintain the printing material in a fluid (e.g., flowable) state and to control the viscosity of the printing material. The printing material may be heated by heating the nozzle which, in turn, transfers heat to the printing material. It has been found that the effectiveness of the nozzle at heating the printing material flowing therethrough (e.g., minimizing a temperature gradient within the printing material) is dependent, at least in part, on the ratio of surface area of the nozzle (e.g., the surface area of the orifice and the conduit surface) that directly contacts the printing material relative to the volume of the conduit. In an example, increasing the surface area of the nozzle relative to the volume of the conduit may make heating of the printing material more effective (i.e., decrease a temperature that the nozzle needs to be heated and/or decrease a temperature gradient within the printing material). In an example, decreasing the surface area of the nozzle relative to the volume of the conduit may make heating of the printing material less effective. In such an example, the nozzlemay need to be heated to a higher temperature to ensure that all of the printing material exhibits at least a certain temperature.

As shown in, the orificemay exhibit a generally circular shape at or near top surface. The conduitof the nozzlemay also exhibit a generally circular shape when intersecting with a reference plane oriented perpendicularly to central axis(“in-plane shape”), since forming the conduitand the orificeto exhibit the same general shape may facilitate manufacturing of the nozzle. A generally circular in-plane shape of the orificeand the conduitof the nozzle, relative to a non-circular in-plane shape, may decrease the surface area of the nozzlethat contacts the printing material relative to a volume of the conduit. As such, in some embodiments, the nozzles disclosed herein may include an orifice and/or conduit exhibiting a non-circular in-plane shape to increase the ratio of the surface area of the nozzle that contacts the printing material relative to the volume of the conduit. For example,are top plan views of a nozzleand a nozzle, respectively, each having orifices exhibiting a non-circular in-plane shape, according to different embodiments. For example, the nozzleis illustrated as having an orificeexhibiting a generally 6-pointed star in-plane shape relative to a central axisand the nozzleis illustrated as having an orificeexhibiting a generally pentagonal in-plane shape relative to a central axis. Although not shown, either of the conduitof the nozzleand the conduitof the nozzlemay exhibit any non-circular in-plane shape, such as an in-plane shape that is substantially similar to the shape of the orifice thereof, respectively, to facilitate manufacturing. The non-circular in-plane shapes of orifices,and conduits,of nozzles,may improve the effectiveness of the nozzles,at heating the printing material flowing therethrough compared to the nozzleillustrated in. It is noted that any of the orifices and/or conduits of any of the nozzles disclosed herein may exhibit any non-circular in-plane shape (other than a generally 6-pointed star in-plane shape or a generally pentagonal in-plane shape), without limitation, such as a generally oblong (e.g., elliptical) in-plane shape, a generally polygonal in-plane shape, a generally semi-circular in-plane shape, a generally triangular in-plane shape, a generally rectangular (e.g., square) in-plane shape, a generally hexagonal in-plane shape, a generally heptagonal in-plane shape, a generally octagonal in-plane shape, a generally 4-pointed star in-plane shape, a generally 5-pointed star shape, or any other suitable non-circular in-plane shape.

As previously discussed, the nozzles disclosed herein may include one or more chamfers extending from the top surface to at least one of the lateral surface or the conduit surface.are cross-sectional schematics of different nozzles that each include chamfers extending from the top surfaces thereof to the lateral surfaces or conduit surfaces thereof, according to different embodiments. Except as otherwise disclosed herein, the nozzles illustrated inmay include one or more features which are the same or substantially similar to any of the features of other nozzle embodiments disclosed herein, without limitation.